I actually have 2 friends (sisters) who a very similar dynamic but with no addiction issues. Learning to say "it's not my problem to solve" wasn't enough for me. I had to stop hearing it all together. When my one friend lost her "venting" friends, her need to be right was less important and powerful. I have seen some very positives changes in their relationship. For me, just my listening to all their "drama" was in still enabling their dysfunction.